Such a valve assembly is partly known from EP patent No. 0.177.620 relating to a pressure medium operated valve with an actuator mounted thereon, but without an actual control unit, the pressure medium connectors communicating directly with the actuator, whereby an elaborate net of pressure medium connectors are required.
The applicant of the present invention has previously used a valve assembly which also comprises a control unit secured to the end of the actuator facing away from the valve by means of screws.
In addition to the pressure medium passage the control unit often comprises solenoid valves with coherent electrical wires having control signals introduced into the control unit.
When a valve assembly is to be serviced it is often necessary to remove the other process equipment from the valve assembly. It is thus necessary to the disconnect the pressure medium supply and the electrical control signal wires. The pressure medium supply, which often is compressed air, is typically discontinued by dismounting and breaking off the hose, while the electrical signal is disconnected by dismounting the wires from a terminal board or by dismantling a plug.